1. Field of the Invention
The present invention relates to the art of steelmaking and particularly the basic oxygen furnace process wherein oxygen is blown into the bath. More specifically the invention relates to a lance particularly designed to blow through the upper opening of a steelmaking vessel gas, oxygen, or other gases for the purpose of removing or retarding the formation of skull which generally is built up on the inner wall of the nose section of the vessel.
2. Description of the Prior Art
Some of the pertinent patents of the Prior Art are U.S. Pat Nos. 3,310,238, Mar. 21, 1967; 3,334,885, Aug. 8, 1967; 3,337,203, Aug. 22, 1967; 3,458,134, July 29, 1969; and 3,960,546 June 1, 1976. U.S. Pat. No. 3,960,546 relates to a process for removing or retarding nose skulls which form in the nose section of the steelmaking vessels. The vessel is of the bottom blow type and includes a number of tuyeres which are mounted at the upper end of the vessel in circumferentially spaced fashion. The tuyeres inject oxygen into the nose section for preventing the build up of nose skulls. The latter patent requires a plurality of pipes or tuyeres and requires the necessity of perforating the nose of the vessel in order to place the tuyeres within the structure, thus having inherent problems which are not found in the present invention. In the present invention a single lance structure is positioned centrally within the charging opening of the vessel.